Elucidation of the ability of activated sludge microbial community to remove hydrogen sulfide from biogas

2022 Fiscal Year Final Research Report

• Project/Area Number: 20K06306
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 41030:Rural environmental engineering and planning-related
• Research Institution: University of the Ryukyus
• Principal Investigator: Yamaoka Masaru 琉球大学, 農学部, 教授 (70373222)
• Project Period (FY): 2020-04-01 – 2023-03-31
• Keywords: メタン発酵 / 硫化水素 / 溶存硫化物 / 活性汚泥

Outline of Final Research Achievements

The purpose of this study was to clarify the removal capacity of hydrogen sulfide by activated sludge for the development of removal technology of hydrogen sulfide in biogas for a methane fermentation facility attached to rural sewage facilities. When biogas was contacted with water or activated sludge, the hydrogen sulfide concentration in the biogas could be reduced to less than 100 ppm depending on the contact area and contact time. This result was considered to be the dissolution of hydrogen sulfide into water or activated sludge. The ratio of dissolved sulfide to dissolved hydrogen sulfide in water or activated sludge was about 30 percent for water and about 3 percent for sludge. The study revealed that activated sludge from rural sewage facilities can be used to remove hydrogen sulfide from biogas.

Free Research Field

農業農村工学

Academic Significance and Societal Importance of the Research Achievements

本研究は、農業集落排水施設の活性汚泥をバイオガス中の硫化水素の除去に利用可能なことを明らかにした。既存のメタン発酵施設での脱硫プロセスは，酸化鉄を主成分とした脱硫剤を消費する乾式法や好気性菌の硫黄酸化細菌を嫌気状態のメタン発酵プロセス内で維持なければならない生物法で，資源消費や維持管理の困難さがあった。本研究結果を基に，排水処理施設の生物反応槽で維持管理されている活性汚泥に硫化水素を溶解させることで硫化水素の分解まで可能であれば，バイオガスの脱硫コストを大幅に低減することが期待できる。